1. Field of the Invention
The present invention relates to a tubular conveyor belt and a method for its manufacture.
2. Description of the Related Art
For conveying bulk material, for example, powders or granular materials, conveyor belts are frequently used onto which the bulk material is placed. These conveyor belts have the advantage that relatively little energy is required for transporting the bulk material. However, the conveyance of bulk material is limited to horizontal routes or to routes with small inclines. In order to overcome greater heights or inclines, it is necessary to transfer the bulk material to another conveyor system, for example, a bucket chain conveyor.
Accordingly, it has been attempted in the past to shape a belt in a hose-like manner and to have the two belt edges overlap each other, so that the bulk material is received in a type of hose. However, it has been found that for maintaining the stability of such a tubular conveyor belt, the belt must be supported by many rollers which may partially even have to be arranged distributed over the circumference of the belt in order to maintain the shape. However, even with such a hose-like conveyor, it is not possible to overcome significant inclines. It is difficult to achieve tightness of the hose, so that a lot of bulk material drops out when the incline is in the range of 30-40.degree..